RF communication systems are well understood in the art. Such systems provide a wide variety of communication services including group voice communications, telephone interconnect, and data communications among many others. It is typical for any given RF communication system to only provide a subset of all possible communication services based on cost, available RF bandwidth, and other factors. Further, within an RF communication system encompassing multiple communication sites, all of the communication services provided by the system may not be available at all sites or at a given site all of the time.
A communication unit, operating in an RF communication system as described, may from time to time request certain communication services. Generally, if the requested service is not available, the request is denied. The user of the communication unit may then choose to repeat the request in other locations or at another time in hopes of gaining access to the requested communication service. It is possible that a large number of subsequent requests may be required before the user succeeds, if in fact success is ever achieved. This process wastes communication resources for the failed service requests, and also contributes to frustration for the user trying to access the communication system.
It should be noted that some prior art communication systems provide for special responses to users when the requested service is only temporarily unavailable. However, these methods apply only to the special case of services that are unavailable for a substantially short period of time.